Substituted 7-acetylamino cephalosporanic acids



this group is matched 3,341,532 SUBSTITUTED 7-ACETYLAMINOCEPHALOSPORANIC ACIDS Benjamin Arthur Lewis, Suifern, and Martin LeonSassiver, Pearl River, N.Y., and Robert Gordon Shepherd, Ridgewood,N.J., assignors to American Cyanamid Company, Stamford, Conn., acorporation of Maine No Drawing. Filed Feb. 15, 1967, Ser. No. 616,170

10 Claims. (Cl. 260-243) ABSTRACT OF THE DISCLOSURE This disclosuredescribes compounds of the class of7-(phenylmalonylamino)cephalosporanic acids,7-(naphthylmalonylamino)cephalosporanic acids, 7-(a-carboX-amidophenylacetylamino)cephalosporanic acids and7-(acarboxamidonaphthylacetylamino)cephalosporanic acids; useful asanti-bacterial agents.

BRIEF SUMMARY OF THE INVENTION This invention relates to new derivativesof 7-aminocephalosporani-c acid and, more particularly, is concernedwith novel compounds which may be represented by the following generalformula:

wherein R is hydroxy or amino; A is acetoxy or N-pyridinium; M ishydrogen, pharmaceutically acceptable non-toxic cations or an anioniccharge when A is N-pyridinium; and Q is l-naphthyl, Z-naphthyl or amoiety of the formula:

wherein R is hydrogen, halogen, nitro or lower alkyl. Suitable loweralkyl groups are those having from 1 t0 4 carbon atoms such as methyl,ethyl, isopropyl, n-butyl, etc. Halogen is exemplified by fluoro, chloroand bromo.

DETAILED DESCRIPTION OF THE INVENTION In the general Formula I set forthabove, in those instances where A is N-pyridinium, the cationic chargeon by the anionic charge of the carboxylic acid radical, the entiremolecule being of a zwitterion nature and M is thus an anionic charge.Typical compounds represented by, the above general Formula I are, forexample,

I 7- (phenylmalonylamino) cephalosporanic acid,

7-(o-chlorophenylmalonylamino) cephalosporanic acid,7-(o-nitrophenylmalonylamino) cehpalosporanic acid, 7-(m-chlorophenylmalonylamino) cephalosporanic acid,

\ 7-(p-isopropylphenylmalonylamino)cephalosporanic acid,

United States Patent Ofifice 3,341,532 Patented Sept. 12, 1967 7-(m-nitrophenylmaloniylamino -3 l-pyridylmethyl 3-cephem-4-carboxylicacid betaine,

7- ot-carboxamidophenylacetylamino) -3l-pyridylmethyl)-3-cephem-4-carboxylic acid betaine, and

7-(tx-carboxamido-l-naphthyl-acetylamino) -3-(1pyridylmethyl)-3-cephem-4-carboxylic acid betaine.

Also embraced within the scope of the present invention are thenon-toxic, pharmaceutically acceptable salts of these derivatives of7-aminocephalosporanic acid. Included are the monobasic salts when R isamino and the dibasic salts when R is hydroxy. The cations comprised inthese salts and embraced by M include, for example, the non-toxic metalcations such as the sodium ion, potassium ion, calcium ion, magnesiumion as well as the organic amine cations, such as the tri(loweralkyl)amine cations (e.g triethylamine), procaine, and the like.

The novel compounds of the present invention, when A is acetoxy inFormula I above, may be readily prepared by acylating7-aminocephalosporanic acid with a com ound of the formula:

wherein R and Q are as hereinbefore defined, and Z is a halide(preferably chloride), azide, acyloxy or p-nitrophenoxy group. Thisacylation of the 7-aminocephalosporanic acid is performed, for example,by the Schotten- Baumann method, taking into consideration thesensitivity of these compounds, under mild conditions and advantageouslyin the presence of a diluent or solvent such such as Water or an organicsolvent, for example, a ketone such as acetone, an ether such astetrahydrofuran, or a halogenated hydrocarbon such as chloroform ormethylene chloride. The reaction is preferably conducted in the presenceof a basic condensing agent such .as sodium bicarbonate or potassiumbicarbonate, or an organic base such as one of the organic bases listedhereinbefore. The reaction is also preferably carried. out at atemperature of from about 0 C. to about 25 C., preferably at 0 C.5 C.,and over a period of time of a few hours or more. Where R is hydroxy,the diacid halide, azide or ester is condensed with7-aminocephalosporanic acid under conditions to give monoacylation andthen hydrolyzed during the work-up and separation of isomers to give thedesired product.

The acylating agents corresponding to Formula II, when new, may beprepared by methods well-known in the art from the corresponding acid (Zis hydroxy). Thus, the acid can be treated with thionyl chloride oroxalyl chloride, if desired in the presence of dimethylformamide, toyield the corresponding acyl chlorides (Z is chlorine), which, ifdesired, can be converted to the acyl azides (Z is N by treatment withsodium azide. The p-nitrophenyl esters (Z is p-nitrophenoxy) can beprepared by following the procedure of Bodanszky et a1. (BiochemicalPreparations, vol. 9, p. 110, 1962, John Wiley and Sons, New York,N.Y.). Specific acylating agents operable in this process (when R isamino) include, for example, a carboxamidophenylacetyl chloride,u-carboxamido-lnaphthylacetyl bromide, u-carboxamido-2-naphthylacetylazide, p-nitrophenyl ot-carboxamido-m-bromo-phenylacetate,a-carboXamido-p-chlorophenylacetyl chloride, and the like. Specificacylating agents operable: in this process (where R is hydroxy) include,for example, phenylmalonic acid diacid chloride, o-chlorophenylmalonicacid diacid bromide, o-nitrophenylmalonic acid diazide,m-chlorophenylmalonic acid di-p-nitrophenyl ester,p-isopropylphenylmalonic acid diazide, m-nitrophenylmalonic acid diacidbromide, l-naphthylmalonic acid diacid chloride, and the like. Theintermediate arylmalonic acids (Z and R are hydroxy) and theintermediate a-carboxamidoarylacetic acids (Z is hydrox-y and R isamino) may be readily prepared from the corresponding arlyacetic acidsand arylacetamides, respectively, by procedures well known in the art.

The novel compounds of the present invention, when A is N-pyridinum inFormula I above, may be readily prepared from the corresponding7-aminocephalosporanic acid derivatives (A is acetoxy in Formula Iabove) by treatment with pyridine in water or aqueous acetone at 2050 C.and for a period of time of about 1-3 days. The resulting3-(1-pyridylmethyl)-3-cephem-4-carboxylic acid betaines may then beisolated by standard procedures of precipitation and crystallization.

Depending on the reaction conditions used, the new compounds of thepresent invention are obtained in the free form or in the form of theirsalts. From the salts it is possible to prepare the acids in knownmanner, or from the acids the salts are readily accessible, for example,by reaction with hydroxides, carbonates or bicarbonates of alkali metalsor alkaline earth metals, or with organic amines.

The novel compounds of the present invention are biologically active andhave been found to possess antibacterial activity. As indicated, theyare useful antimicrobial agents and have broad-spectrum antimicrobialactivity in vitro against standard laboratory microorganisms used toscreen for activity against pathogens. The antibacterial spectrum of atypical compound of the present invention, representing theconcentration required -to inhibit the growth of various typicalbacteria, was determined in a standard manner by the agar-dilutionstreak-plate technique which is commonly used in testing newantibiotics.

The following table summarizes the in vitro activity of7-(phenylmalonylamino)cephalosporanic acid (1) as compared withCephalosporin C (2) against a variety of disease-causing microorganisms.

Minimal inhibitory cone. (meg/ml.) Organisms Staphylococcus aurcus N0.11 1. 56 100 Staphylococcus aureus ATCC 13709 0. 39 50 Streptococcuspyrogcncs -203 0. 39 25 Bacillus ccreus ATCC 10702 1. 56 100 Salmonellatyphosa ATCC 6539. 6.25 12. 5 Proteus mirabilis ATCC 9921. 12. 5 25Escherichia co t ATCC 9637.. 100 50 Klebsiclla pneumomae KAD 12. 5 25Shigella shz'ga 6. 25 25 Example 1.Prcparati0n of7-(phenylmalonylam'ino) cephalosporanic acid Phenylmalonic acid (360mg., 2 mmole) was converted to its diacid chloride with oxalyl chloride.The diacid chloride in acetone (20 ml.) was added to a stirred solutionof 7-aminocephalosporanic acid (545 mg, 2 mmole) and sodium bicarbonate(672 mg, 8 mmole) in water (40 ml.) and acetone (20 ml.) which was keptd between 0 C. and 5 C. The reaction was stirred for 2 hours at thistemperature, and then the acetone was removed under reduced pressure.The aqueous solution was acidified to pH 1 with hydrochloric acid andthe mixture extracted with ethyl acetate (3X 50 ml.), the ethyl acetatesolution was washed with water (100 ml.) and dried over magnesiumsulfate. Evaporation of the solvent under reduced pressure gave7-(phenylmalonylamino)cephalosporanic acid. The sodium salt was obtainedby slurrying this product in water (10 ml.) and adding 2 N sodiumhydroxide dropwise to pH 5 to effect solution. The solution wasconcentrated to small volume in a rotary evaporator at 50 C., and thesodium salt was precipitated by the addition of acetone. The precipitate.was collected by filtration and dried to give 715 mg. of the disodiumsalt of 7-(phenylmalonylamino) cephalosporanic acid as an ivory solid.

Example 2.Prepzrration 0f 7-(d-COIbOXIZmidOPhQHYZ- acetylaminocephalosporanic acid Example 3.Preparwtion of7-(m-chlorophenylmalonylamino) cephalosporanic-acid The procedure ofExample 1 is repeated, substituting an equimolecular amount ofm-chlorophenylmalonyl dibromi-de for the phenylmalonyl dichlorideemployed in that example. There is thus obtained the 7-(m-chlorophenylmalonylamino)cephalosporanic acid.

Example 4.Preparati0n of 7-(ct-carboxamido-o-bromm phenylacetylamino)cephalosporanic acid In place of the phenylmalonyl dichloride of Example1, there is employed an equimolecular quantity ofa-carboxamido-o-bromophenylacetyl azide whereby the 7 (a carboxamido obromophenylacetylamino) cephalosporanic acid is obtained in equally goodyield.

Example 5.Preparati0n of 7-(o-nitrophenylmalonylamino) cephalosporanicacid In the manner described in Example 1, treatment of7-aminophalosporanic acid with o-nitrophenylmalonyl V dichlorideproduces the 7-(o-nitrophenylmalonylamino) cephalosporanic acid.

Example 6.Preparati0n of 7-(phenylmal0nylwmin0) -3- (1 -pyridy lmethyl-3-cephem-4-carb0xylic acid betaine One gram of the sodium salt of7-(phenylmalonylamino)cephalosporanic acid and 8 ml. of pyridine wasdissolved in 50 ml. of water, which was adjusted to pH 6 with aceticacid, and stored under nitrogen for 3 days at 37 C. The solution wasevaporated to dryness and the residue was triturated with acetone togive the product.

Example 7. Preparation of 7-(ot-carb0xamid0phenylacetylamino) 3 (1pyridiylmethyl) 3 cephem- 4-carb0xylic acid betaine Example8.Preparati0n of 7-(l-naphthylmdlonylamino cephalosporanic acid Byreplacing the phenylmalonyl dichloride employed in Example 1 with anequimolecular quantity of l-naphthylmalonyl dichloride and followingsubstantially the same procedure described in Example 1, there isobtained the 7-(l-naphthylmalonylamino)cephalosporanic acid.

Elmmple 9.-Preparation of 7-(Z-naphthylmalonylamino) ceplzalosporanicacid The procedure of Example 1 is repeated, substituting anequimolecular amount of 2-naphthylma1onyl dichloride for thephenylmalonyl dichloride employed in that example. There is thusobtained the 7-(2-naphthylmalonylamino)cephalosporanic acid in equallygood yield.

What is claimed is:

1. A compound selected from the group consisting of those of theformula:

wherein R is selected from the group consisting of hydrogen, halogen,nitro and lower alkyl; and the non-toxic pharmaceutically acceptablebasic salts thereof when R is hydroxy.

2. A compound according to claim 1 wherein R is hydroxy, A is acetoxy, Mis hydrogen and Q is phenyl.

3. A compound according to claim 1 wherein R is hydroxy, A isn-pyridinium, M is an anionic charge and Q is phenyl.

4. A compound according to claim 1 wherein R is amino, A is acetoxy, Mis hydrogen and Q is phenyl.

5. A compound according to claim 1 wherein R is amino, A isN-pyridinium, M is an anionic charge and Q is phenyl.

6. A compound according to claim 1 wherein R is hydroxy, A is acetoxy, Mis hydrogen and Q is meta-chlorophenyl.

7. A compound according to claim 1 amino, A is acetox-y, phenyl.

8. A compound according to claim 1 wherein R is hydroxy, A is acetoxy, Mis hydrogen and Q is ortho-nitrophenyl.

9. A compound according to claim 1 wherein R is hydroxy, A is acetoxy, Mis hydrogen and Q is l-naphthyl.

10. A compound according to claim 1 wherein R is hydroxy, A is acetoxy,M is hydrogen and. Q is Z-naphthyl.

wherein R is M is hydrogen and Q is ortho-bromo- References Cited UNITEDSTATES PATENTS 3,225,038 12/1967 Flynn.

NICHOLAS S. RIZZO, Primary Examiner.

1. A COMPOUND SELECTED FROM THE GROUP CONSISTING OF THOSE OF THE FORMULA